Time delay relay



Jan. 5, 1937. c. c. RALPH 2,066,575

TIME DELAY RELAY Filed Aug. 11, 1954 2 Sheets-Sheet 1 3 M Hum 9 1 (IIIN/E/VTU c c. RAL

)4 TERA/E Jan. 5, 1937. c. CRALPH 2,066,575

TIME DELAY RELAY I Filed Aug., 11, 1934 2 Sheets-Sheet 2 Mu/ENTUR Wg 5C..C..RALPH )4 *TURNE Patented Jan. 5, 1937 v 2,066,575 v UNITED STATESPATENT OFFICE 2,066,575 TIME DELAY RELAY Charles C. ltalphylortland,Oreg. Application August 11, 193 4, SerialNo. 739,390

1 Claimc1. zoo-9'1) This invention relates generally to switching Fig.11 is similar to Fig. 10 but showing the devices, and particularly to atime delay relay. maximum amount of resistance offered to the The mainobject of this invention is the conflow of current. struction of athoroughly reliable and inexpensive Fig. 12 is a section through thepoint of a contime delay relay by means of which there may tact screw.

be interposed a deflnite lag in the opening or 0105- Similar numbers ofreference refer to similar ing of one or more electrical circuits afterthe parts throughout the several views. opening or closing ofanother,circuit. Referring in detail to the drawings, there is Thesecond object is to provide a time delay shown a tubular shell l2 offerrous metal whose relay which is independent of temperature conlowerend I3 is of a similar material and has 10 ditions and which can be setwith extreme acmounted on the center thereof a magnet core l4 curacy.whose upper end l5 extends through the floor IS The third object is theutilization of mercury of insulating material which flts tightly withinin the .switching element and the provision of the shell l2 and forms awell for mercury I1. means for protecting the mercury against oxida-Between the lower end l3 and the floor i6 and 15 tion under-atmosphericand arcing conditions. surrounding the core I4 is the electromagnet 18The fourth object is to utilize the well known to which current issupplied from a source of enaflinity between mercury and certain othermetals, ergy, such as a battery l9, through the lead wires such ascopper, in order to obtain a rapid sep- 20. The flow .of current to themagnet 18 is aration of the switching points when the circuit controlledby means of a switch 2| which maybe 20 is broken. either manuallyoperated or responsive to time,

The fifth object is to provide a construction temperature, or otherconditions. which will improve the action of the solenoid. Within theshell l2 and floating in the mer- The sixth object is to provide a formof relay cury I1 is an open float 22 having a recess 23 in adaptable forcontinuous use in controlling deits top side. -The float 22 ispreferably provided 5 vices-operated from ordinary lighting circuits.with non-ferrous rings 24 and 25 which hold the.

These, and other objects, will become more I float 22 out of intimatecontact with the shell l2. apparent from the specification following asil- Extending upwardly through the ring 24 and into lustrated in theaccompanying drawings, in the float 22 are the vertical holes 25 whichcom-- which: municate by means of the inclined holes 21 with 30 Fig. 1is a diagrammatic view showing the manthe recess 23. ner of connecting aplurality of lights to the re- In the bottom 28 of the float 22 ismounted lay. a bushing 29 made of copper, or some other suit- Fig. 2 isavertical section through the preferred able metal, and having a hole 30formed thereform of the device showing the relay closed. through. 35

Fig. 3 is similar to Fig. 2 but showing the relay The top of the shellI2 is closed by means of a open. head 3| of insulating material in whichare Fig. 4 is a vertical section through a modified mounted ,variouscontact screws 32, 33, 34, 33, form of the device employed for handlingthe cur- 36, 31 and 38, the lower end of each of which m rent from alighting circuit. I is provided with a copper tip 39 (as shown in m Fig.5 is a side elevation of the rotor illustrated Fig. 12). in Fig. 4, aportion of which is broken away'in sec- It will be seen in Fig. 1 thatthe contact screws tion and showing the circuit open. 32, 33,, 34 and 35inclusive are connected to the Fig. 6 is similar to Fig. 5 butshowingthe rotor lamps 40, 4!, 42 and 43. This, however, is meretiltedand the circuit closed. ly for the purpose of illustration since theyare Fig. 'lis a vertical section through a simple capable of beingconnected in any other manform of the device showing the circuit closed.ner desired, and the screws 36 to 38 may be con- Fig. 8 is similar toFig. 7 showing the circuit nected to other lamps or apparatus'ifdesired. about to be broken. The lamps 40 to 43 are connected to thebattery Fig. 9 is similar to Fig. 8 showing the circuit IS. The batteryi9 is also connected by means completely broken. of a wire 44 to thebottom end l3.

Fig. 10 is a view through a modification oi the The operation of thisform of the device is as device inwbich it isused to operate a rheostatand follows: Assuming that the switch 2| is closed, ini'whichtbe amountof resistance is either manually or automatically, as the result- 5.offered to the flowoi current. of a thermostatic action, or by a timeswitching mechanism, or in any other manner which will permit current toflow to the magnet 6, thus overcoming the balance of buoyancy of thefloat 22 and submerging it in the mercury I1, forcing the mercury upthrough the holes 26, then through the holes 21 into the recess 23, someof the mercury also passing upwardly through the small hole 30.

The submerging of the float 22 has brought about a rise in the level ofthe mercury H which now surrounds the lower ends of the screws 32 to 36.It will be understood that the float 22 is in reality the armature forthe magnet l6 and will descend when the magnet I6 is energized, or riseto a floating position when the magnet i8 is not energized.

The various lamps 46 to 43 will remain lighted as long as the switch 2|remains closed, and in addition thereto until the mercury H has had timeto pass downwardly through the small opening 36, thereby permitting thefloat 22 to rise and displace less of the mercury thereby uncovering thevarious screw points 33 in the order of their elevationthat is, thehighest point 36 for example, will be uncovered flrst and the lowestpoint 32 will be uncovered last. 1

It willbe observed that the rapidity of the 'operation is controlled toa large extent by the size of the openings 26, 21 and 36, while thetiming may be accurately controlled by the setting of the various screws33 to 36.

In the form of the device shown in Figs. 4 to 6 the same armature orfloat 22 is employed, as well as the magnet l8 and shell l2. With thisform of the device, however, is employed a gas filled orevacuated sphere45 which is rockably mounted on the metallic trunnions 46 which journalin the brackets 41 and 46, which are separately mounted on the underside of the head 49 made of insulating material.

The brackets 41 and 46 are joined by the wires 56 and 5| to a motor 52which is connected to a power circuit 53. Within the sphere 45 is a dam54 which, like the sphere 45, is made of an insulating material such asglass. The dam 54 is normal to the axis of the trunnions 46.

Connected to the trunnions 46 and extending into the sphere 45 are theelectrodes 55 which.

extend almost to the dam 54, somewhat near one end thereof. A trunnion46 is provided with a crank 56 which is joined by a connecting rod 51 toan eye 56 secured to the float 22, preferably near the middle thereof.

The operation of this form of the device is as follows: When the switch56 is closed and the float 22 submerged the sphere 45 is rocked on itsaxis to the position shown in Fig. 6, permitting current to flow betweenthe electrodes 55 through the mercury 60, however when, the switch 69 isagain opened and when enough mercury H has passed downwardlythrough thehole 36, thereby permitting the float or armature 22 to rise, then thesphere 45 isreturned to its original position (as shown in Fig. 5).

The point to be observed here is that when the break in the circuit ismade it occurs from the dam 54, and this break is very rapid and a verysmall amount of power is required to rock the sphere 45 as compared withthe mercury switches of the tilting tube type.

In the form of the device shown in Figs. '7 to 9 a simple form of floator armature 6| is illustrated and there is provided sufllcient clear-.

ance 62 around the float 6| to permit the rapid upward movement of themercury ll. In this form of the device a single electrode screw 63 isillustrated, and there is also shown the use of the oil fllm 64 on thesurface of the mercury H, the purpose of which is to reduce oxidationeither from atmospheric conditions or from arcing conditions.

It will be noted that the screw 63 is provided with a copper tip 33whose afllnity for the mercury causes it to form a connecting column 65(as shown in Fig. 8); however, when the column 65 has reached itsmaximum length it severs very rapidly, bringing about a very desirableaction for the circuit breaker.

In the form of the device shown in Figs. 10 and 11 instead of employingthe contact screws 32 to 36 or the rockable sphere 45, there isillustrated the use of a rheostat which consists of a simple resistancecoil 66 which is suspended from the head 61 by means of the screws 68and 69.

It can be seen that in this form of the device the flow of current tothe lamp'lll may be variably controlled, since the resistance offered bythe element 66 is effected by the amount which is shorted out by themercury II.

It will be noted that plug 29 is preferably made of copper or some metalwhich will amalgamate with mercury and this plug has a small hole 36drilled therethrough. The side 01 this hole amalgamates with the mercuryand offers a capillary attraction which aids in the flow of mercurythrough the hole, thus permitting the use of a very minute hole that isat all times covered with mercury preventing any possibility of foreignsubstances clogging the hole.

The use of this plug increases the efllciency ot the device by allowingdelays on a small relay up to five minutes, whereas the greatestpossible delay without the amalgamating plug will be about flve seconds.

The amalgamated tip 39 allows a delay on the return of the armature toits floating position. This feature of the relay makes it automatic inaction whereby it will cause a continuous recycling action of thearmature with a predeter-- mined time delay both on the closing and theopening oi the circuit.

In other words, it is the combined action of the amalgamated plug and.the amalgamated tip which makes possible the abnormally long delayinterval obtainable with this relay.

I claim:

A time delay relay comprising a mercury bath, an armature in the form ofa container adapted to float in said bath, said armature having anopening in the bottom thereof through which mercury can pass to or fromthe interior of the armature, an electromagnet associated with saidarmature for exerting a pull thereon for the purpose oi submerging saidarmature, the emerging action being retarded by the.flow of mercurythrough said opening and a mercurial switch in the form of a sphererockably mounted on a horizontal axis and having a dam across the lowerportion thereof normal to its axis, said switch having spaced electrodestherein separated by said dam and having a body of mercury confinedwithlnsaid sphere, together with means for rocking said sphere toconform with the movements of said armature.

CHARLES C. RALPH.

